staging/comedi: Use dev_ printks in drivers/ni_pcimio.c

fixed below checkpatch warning.
- WARNING: Prefer netdev_warn(netdev, ... then dev_warn(dev, ... then pr_warn(...  to printk(KERN_WARNING ...
Signed-off-by: YAMANE Toshiaki <yamanetoshi@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_pcimio.c

@@ -1384,8 +1384,9 @@ static void m_series_stc_writew(struct comedi_device *dev, uint16_t data,
 		/* FIXME: DIO_Output_Register (16 bit reg) is replaced by M_Offset_Static_Digital_Output (32 bit)
 		   and M_Offset_SCXI_Serial_Data_Out (8 bit) */
 	default:
-		printk(KERN_WARNING "%s: bug! unhandled register=0x%x in switch.\n",
-		       __func__, reg);
+		dev_warn(dev->class_dev,
+			 "%s: bug! unhandled register=0x%x in switch.\n",
+			 __func__, reg);
 		BUG();
 		return;
 		break;
@@ -1421,8 +1422,9 @@ static uint16_t m_series_stc_readw(struct comedi_device *dev, int reg)
 		offset = M_Offset_G01_Status;
 		break;
 	default:
-		printk(KERN_WARNING "%s: bug! unhandled register=0x%x in switch.\n",
-		       __func__, reg);
+		dev_warn(dev->class_dev,
+			 "%s: bug! unhandled register=0x%x in switch.\n",
+			 __func__, reg);
 		BUG();
 		return 0;
 		break;
@@ -1465,8 +1467,9 @@ static void m_series_stc_writel(struct comedi_device *dev, uint32_t data,
 		offset = M_Offset_G1_Load_B;
 		break;
 	default:
-		printk(KERN_WARNING "%s: bug! unhandled register=0x%x in switch.\n",
-		       __func__, reg);
+		dev_warn(dev->class_dev,
+			 "%s: bug! unhandled register=0x%x in switch.\n",
+			 __func__, reg);
 		BUG();
 		return;
 		break;
@@ -1493,8 +1496,9 @@ static uint32_t m_series_stc_readl(struct comedi_device *dev, int reg)
 		offset = M_Offset_G1_Save;
 		break;
 	default:
-		printk(KERN_WARNING "%s: bug! unhandled register=0x%x in switch.\n",
-		       __func__, reg);
+		dev_warn(dev->class_dev,
+			 "%s: bug! unhandled register=0x%x in switch.\n",
+			 __func__, reg);
 		BUG();
 		return 0;
 		break;